One of my heroes passed this week, the brilliant British science fiction author John Christopher, 89, best known for his Tripod trilogy which has been amazing young readers for more than 40 years. (Read the first chapter here.)

The three books — The White Mountains, The City of Gold and Lead, and The Pool of Fire offered my generation of young-adult sf fans a powerful mix of alien invasion, thought control, organized rebellion, and post-apocalyptic shocks-of-recognition. (OMG! Chemin de fer! Holy crap! Panama! )

Like much of the sf writing of the day, some aspects haven't aged quite as well — it's a boys novel that doesn't have the diverse cast we expect in today's fiction — but what's there is rock solid sf, which gazes with unblinking steadiness at the horror of human subjugation and death. Looking back as an adult, it's easy to nod and thoughtfully classify this as a highly-encrypted alternate post-WWII England, but when I read it for the first time, at about 10 years old, it just took the top of my head off and poured in a steady stream of cognitive estrangement. It is not too much to say that my interest in media theory dates back to this book, and Neil Postman would have found Christopher's explanation for the ease of the Tripod's takeover quite sensible.

Sf has lost another golden age writer who shaped our field. Thanks, Mr. Christopher. We shall do our best to pay it forward.

Read appreciation at io9 and obit at the New York Times.